Etherification over Hβ zeolite modified by lanthanum ion exchange combined with low-temperature steam treatment

Abstract

Lanthanum ion exchange, low-temperature steam treatment and La/steam combined modification were used to modify Hβ zeolite, and then comparative studies were performed on the influences of single and compound modified methods on the etherification activity. XRD, XRF, BET, FETEM-EDS, FTIR, OH-FTIR, NH₃-TPD and Py-IR analysis methods were used to characterize the catalysts. The evaluation results show that the best modification method is lanthanum ion exchange followed by low-temperature steam treatment; the highest conversion of isoamylene was 67.72% and the yield of TAME was 65.63%. The characterization results implied that large pore sizes, high acidity, moderate acid strength and a suitable Brønsted acid proportion are all favourable for etherification.